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Murder by Death is a 1976 American mystery comedy film written and directed by Robert Moore. The film stars Peter Falk, Maggie Smith, Elsa Lanchester, David Niven, Peter Sellers, Alec Guinness, and Eileen Heckart. The film is a spoof of Agatha Christie-style whodunits, featuring a group of eccentric detectives gathered at a mansion to solve a murder. Falk plays Sam Diamond, a cynical private detective.